Drought stress in crop plants causes widespread yield loss. In addition, other abiotic stress such as low nitrogen also affects crop growth and yield. Improving agronomic traits in crop plants is beneficial to farmers. Several factors crop yield. Abiotic stress is the primary cause of crop loss worldwide, causing average yield losses of more than 50% for major crops (Boyer, (1982) Science 218:443-448; Bray, et al., (2000) In Biochemistry and Molecular Biology of Plants, Edited by Buchannan, et al., Amer. Soc. Plant Biol., pp. 1158-1249). Among the various abiotic stresses, drought is a major factor that limits crop productivity worldwide. Exposure of plants to a water-limiting environment during various developmental stages appears to activate various physiological and developmental changes. Molecular mechanisms of abiotic stress responses and the genetic regulatory networks of drought stress tolerance have been studied (Valliyodan, and Nguyen, (2006) Curr. Opin. Plant Biol. 9:189-195; Wang, et al., (2003) Planta 218:1-14); Vinocur and Altman, (2005) Curr. Opin. Biotechnol. 16:123-132; Chaves and Oliveira, (2004) J. Exp. Bot. 55:2365-2384; Shinozaki, et al., (2003) Curr. Opin. Plant Biol. 6:410-417; Yamaguchi-Shinozaki and Shinozaki, (2005) Trends Plant Sci. 10:88-94).
Various transcription factors (TFs) have been reported to be associated with a response to abiotic and biotic stress in plants. For example, the drought-responsive element (DRE) binding proteins (DREBs) or C-repeat (CRT) binding factors (CBFs), and the ethylene response factors (ERFs) are such transcription factors. The CBF/DREB proteins can regulate the expression of drought/cold stress-related genes by binding to a CCGAC core motif, while the ERF TFs are known to bind to the GCC box (GCCGCC). Both families of proteins contain the Apetala2 (AP2) domain, while the CBF/DREB proteins are distinguished further by the presence of two regions, PKKP/RAGRxKFxETRHP (SEQ ID NO: 21) (abbreviated PKKPAGR) and DSAWR (SEQ ID NO: 22), which are located immediately upstream and downstream, respectively, of the AP2/ERF DNA-binding domain. Jaglo et al (2001) Plant Physiol. 127:910-917; Canella et al. (2010) Biochim. Biophys. Acta. 1799(5-6):454-462. Although ERF proteins are generally known to bind the GCC box, at least two ERFs, one from pepper and the other from wheat, have been shown to associate with both the GCC box and the CRT/DRE element.
Expression of the dehydrin gene family, a class of Late Embryogenesis Abundant (LEA) proteins, is regulated by exposure to abiotic stress. The promoters of genes encoding dehydrins are strongly activated in vegetative tissues under stress conditions. cis-acting elements and respective TFs responsible for the constitutive and stress-inducible activation of either Wcor410 or Wcor410-like genes from other plants than those mentioned previously, have not yet been reported. The Wcor410 gene from wheat was originally identified as a gene encoding a LEA protein that accumulates to equal levels in root, crown and leaf tissues of freezing-tolerant Gramineae during cold acclimation.
ERF transcription factors, uses thereof and analysis of promoters are presented herein.